This invention relates to a dispensing device for flowing substances.
There is a great need of efficient dispensing devices for various different types of flowing substances. Food products, such as mustard, ketchup, dressings and so on within the restaurant and kiosk business, cream, butter creams, jams and so on within the bakery business, liquid soap and other cleaning products and so on, may be mentioned as examples. The dispensing devices known are affected by drawbacks with respect to the valve arrangement for regulating flow of substance and the operating means for the valve arrangement. More exactly one problem resides in obtaining an acceptable compromise with respect to tightness in closed position and easiness with respect to the power required for dispensing, i.e. the power or force required for deforming the flexible tube and operating the valve arrangement. It is namely here assumed that operating the valve arrangement and by that controlling the very dispensing is carried out by the operator pressing the flexible tube together by his hand. An additional problem of known constructions of the valve arrangement is that they are not particularly well suited for such situations in which there is always an overpressure in a conduit or container upstream of the flexible tube generated by a pump controlled by means of a pressure sensor.
The handling now used for food products of additive character for the food industry, e.g. bakeries etc., and the restaurant business is affected by several deficiencies. Thus, it is today usual that the containers containing the food product in question are located in a position at room temperature for hours, or days, or even weeks before the content of the containers has been consumed. Furthermore, such considerable lengths of time also often pass between thoroughly cleaning of the containers and the dispensing devices used. Such extended dwell times of food products at room temperature give rise to a rapid increase of micro organisms harmful to humans. It is true that attempts are made to reduce this increase by admixing considerable quantities of pesticides against the micro organisms in question to food products in question. However, it is today a nearly unanimous opinion within the staff of medical researchers within this field that such pesticides are considerably more harmful to the human organism than expected before. When the content of pesticides is reduced or such means are totally eliminated, an even more rapid increase of micro organisms is created.